What?

Closes #71740

Adds "role": "content" to the title attribute in the accordion header block to make it editable when templateLock: "contentOnly" is applied to parent blocks.

Why?

When an Accordion block is wrapped with a Group block that has templateLock: "contentOnly" applied, users cannot edit the accordion header text.

How?

Added "role": "content" to the title attribute of accordion header block

Testing Instructions

1. Create a new post or page in the block editor.
2. Insert a Group block.
3. Inside the Group block, add an Accordion block.
4. Apply 1"templateLock": "contentOnly"` to the Group block (parent container).
5. The accordion header text should remain editable.

Screenshots

Before	After